The invention relates to selective plating, in particular the selective plating of components such as connectors with electrodepositable metals and alloys such as gold.
In a previously proposed method for the selective plating of connectors with gold, a plurality of connectors make up a reel which is indexed in plating heads sliding on tracks over a plating tank, each plating head comprising means, for example a lower mask, for exposing a selected portion of each connector to electrolyte and a resilient backing member for releasably sealing the rear of the reel during plating. An elongate slot jet locates between the tracks. An apparatus for carrying out the method is described and illustrated in U.S. patent application Ser. No. 06/333,692 (Cockeram), now U.S. Pat. No. 4,414,075.
Other methods have also been previously proposed for plating onto a contact face using top and bottom masks. However, previously proposed methods have suffered from the disadvantage that the edges of the components being plated remain unmasked and are therefore plated unnecessarily. The metal deposited on the component edges can comprise about 30% of the total weight of metal plated (depending on the shape of the component) and is not required for functional purposes. Large amounts of gold (or other metal) are thus wasted.